Updated parse sorting method to support coalesce sorting with multiple columns, by extending the current sortExpr with modifier and multiple columns, IE. `coalesce` as modifier and given arguments will be multiple columns for the sortExpr.
Also, updated cursor to support modifier and multiple column support along with rdbms.go.tpl for the same.
We removed handle requirement for all resource like namespace(slug), module, user, page, chart.
Due to that namespace import/export was broken as we were using handle as reference, hence fixed it by replacing handle usage with ID of resource.
It also fixes index of template table for handle column.
